This then means any Mac you connect to the display, via the single Thunderbolt connection already on the display (which works at 10,000Mpbs [aka 10Gbps] so has plenty of bandwidth to handle Gigabit Ethernet easily, along with any other devices you plug into the other ports on the back of the display!) has access to the network (both your home network devices and internet).

This is useful if you had bad Wi-Fi coverage, and wanted a decent wired connection instead. For laptops, you could use Wi-Fi when not near the display, and then use a wired connection when using the display.

(2) Device connection.
Another alternative is just to connect a NAS drive (which often only have Ethernet connections, rather than USB/FW ones) into the back of the display via an Ethernet cable, and then connecting the display to a Mac via that single Thunderbolt cable to have access to the NAS.

(Hopefully in a revision, they could make the power directly MagSafe 2 (no adaptor thus needed), the USB2's to USB 3's (at least one/two of the three on it), and make the Ethernet port another Thunderbolt port for extra Thunderbolt device options (users could instead use the new Thunderbolt to Gigabit Ethernet adaptor, should they wish) All sensible, but we'll see. :-)

Probably the main two things, though there may be other specialist ones I can't think of, off the top of my head.